Driver contact vibrator



Aug.. 17, 1948. R. J. AUST DRIVER CONTACT VIBRATOR Filed lay 26. 1944 Patented Aug. 17, 1948 annoia Dnrvna coN'rAc'r vrnaA'roa Robert J. Aust, Indianapolis, Ind., signor to P. B..

Mallory Co., Inc., Indlanapolb, Ind., a corporation o! Delaware Application May 26, 1944, Serial No. 537,464

'lClalmll The present invention relates to vibratory electromagnetic interrupters, and, more particularly, to a driver contact vibrator of novel and improved character.

As those skilled in the art know, conventional driver contact vibrators generally include a main reed bearing vibratory contacts and an auxiliary reed bearing a driver contact. According to current practice, the auxiliary reed is integrally formed with the main reed and is defined by means of a U-slraped slot stamped therein, or the auxiliary reed is provided in the form o! a separate element secured at one end to the main reed and-having its other end extending into a. longitudinal slot stamped in the main reed in the center portion thereof. This type of construction was connected with various disadvantages. Thus, the provision of the auxiliary or driver contact reed has considerably weakened the main reed in the portions where it is most subjected to bending stresses. In addition, the provision of holes or slots in the said portions of the main reed involved complicated stamping operation and the percentage of rejects due to faulty dies was high. Moreover, the concentration of stresses in the weakened critical regions of the main reed was a frequent cause of reed failure and of operating difnculties. Although these diillculties were well known in the art and various suggestions and proposals were made to solve the outstanding,

problem, as far as is known, none of these suggestions and proposals was completely satisfactory and successful when carried into practice on a practical and commercial scale.

Itis an object of the present invention to eliminate the foregoing diiliculties and inconveniences experienced in the construction of driver contact vibrators.

It is another object oi' the present invention to provide a driver contact vibrator of novel and improved character in which there are no holes or slots provided in the critical regions of the main reed so that the full structural strength of the reed material is retained in said regions.

It is a further object of the invention to provide a novel `structural and mechanical organization for a driver contact vibrator including a tapered main reed having a substantially continuous and imperforate surface in the regions where the principal bending stresses are present and a separate asymmetrically mounted auxiliary reed bearing the driver contact and cooperating with the main reed under the control thereof to operate the driver circuit. Y

It is also within the contemplation of the invention to provide a driver contact vibrator in which the auxiliary reed is substantially independent from the imperforate main reed and is mounted laterally thereof, means being provided to control the break" of the driver circuit in accordance with the operation oi' the main reed.

The invention also contemplates a driver contact vibrator of novel character which is simple in structure, reliable in operation, easy to adjust. and which may be readily manufacturedv on a practical and commercial scale at a low cost.

Other and further objects and advantages of the invention will become apparent from the iollowing description, taken in conjunction with the accompanying drawings; in which Fig. 1 illustrates a, front elevational view of a preferred embodiment of the invention;

Fig. 2 depicts a side elevational view of the vibrator shown in Fig. 1

Fig. 3 shows a perspective view of the vibratory system of the vibrator illustrated in Figs. 1 and 2.'

Fig. 4 is a front elevational view of a modiiled vibratory structure;

Fig. 5 is a side elevation of the vibratory structure shown in Fig 4;

Fig. 6 is a front elevation of another modified vibratory structure adapted to be employed in combination with a vibrator embodying the invention; and

Fig. 7 is a side elevation of the vibratory structure of Fig. 6.

While a. preferred embodiment of the invention is described herein, it is contemplated that considerable variation may be made in the method of procedure and the construction of parts without departing from the spirit of the invention. lIn the following description, and in the claims, parts will be identied by specific names, for conveniencabut they are intended to be as generic in their application to similar parts as the art will permit.

Referring now more particularly to Figs. l to 3 of the drawings, reference character I0 denotes a hook-shaped ferromagnetic frame having a narrowed hook portion I i around which there is provided a driver coil I2. A stack generally denoted by reference character I3 lis secured to the lower extremity of frame ill by means of stack screws I4 and nuts I5. Progressing from the frame, the stack comprises a pair of metal spacers It, an insulative spacer I1, a pair of side springs Il, a pair of insulative spacers i! between which there is clamped the lower extremity 20 of the main reed, a pair of side springs 2|, an insulative spacer 22, and metal spacers 23. All of the spacers are provided with aligned holes through which the stack screws i4 may extend, said holes being sufciently large in diameter to accommodate insulative bushings (not shown) around the screws to insulate the several elements from each other and from the frame in the usual manner. Side springs 2| and I8 carry relatively xed contacts 24 and 25, respectively, at the ends thereof, for cooperation with the vibratory contacts of the main reed, as it will appear presently.

The structure of the vibratorysystem will be best understood from Fig. 3. It will be noted that this system is built around an upwardly tapering main reed 26 having its upper end 2l formed with transverse extensions and having holes 23 for the stack screws in its lower or clamped portion 2li. A transverse slot 29 is stamped in an intermediate region of the reed immediately above the clamped region and defines hinges 3G, A pair of integrally formed U-shaped side arms 3| and 32 are secured to each side of the main reed by means of rivets or spot welds 33, of which 3| carries vibratory contacts 34 at the ends of thereof and 32 carries vin bratory contacts 35 at the ends thereof. Driver contact 36 is mounted at the end of auxiliary reed 31, the lower end of which is integrally formed with a lateral extension 38, riveted or otherwise secured between the main reed 26 and the lower portion of side arm 3|. To the upper portion 21 of main reed 26 there is secured an armature or weight 39 which is slightly narrower than element '21 so that there is a narrow ledge d0 provided above which the end of auxiliary reed 31 may extend. Vibratory driver contact 36 is adapted to cooperate with a normally closed stationary driver contact 4| at the end of a screw 42 adjustable in a threaded hole in frame ill whereby the driver contact system may be readily adjusted for optimum operation. VThe vibrator is connected in the conventional manner by means of exible conductors 43 to contact prongs 44 depending from an insulative disc 45, forming the base plate of the vibrator. In accordance with usual vibrator practice, the vibrator may be covered with a circular metal can (not shown) lined with sponge rubber and having its bottom edges crimped aroundthe circumferential edges of disc 45.

From the foregoing description, th'e operation of the vibrator of the invention will be readily f understood by those skilled in the art. The circuit organization being of a conventional character does not require any detailed description. It will be sufcient to state that the several contacts are so adjusted that in the normal position of rest the interrupter and the rectifier contacts are open and the driver contacts are closed. The relatively fixed interrupter contacts are connected to the two ends of the primary winding of a step-up transformer, the relatively fixed rectifier contacts are connected to thetwo ends of the secondary winding of said transformer, a source of low voltage current is connected between the center tap of the primary winding and the main reed, and the rectied high-voltage output is taken oi between the center tap of the secondary winding and the reed. The driver circuit comprises the driver contacts connected in series with the driver coil and the source of current.

Upon closing the circuit of the vibrator, the driver circuit will be energized and driver coil I2 will attract armature 39 thereby deecting the main reed 26. A' predetermined time interval thereafter ledge 49 of the armature will strike against the upper extremity of auxiliary reed 31 and will break the driver circuit. The inertia Qf the vibratory system, however, will cause continuation of the displacement of the armature and of the main reed in the same direction until the interrupter and rectifier contacts are closed for a short period of time. The resiliency of the main reed will now return the vibratory structure in the opposite direction past the center position thereof until the other set of interrupter and recnner contacts will be momentarily erased. The compliance and the natural frequency of auxiliary reed 31 is so determined that it Will slightly lag behind the main reed during the returntravel thereof so that the driver circuit will be again closed lbetween driver contacts 36 and 4| at the proper. time and will again deflect the main and the auxiliary reeds by means of the energized driver coil.

The modined embodiment of a vibratory structure shown 1n Figs. 4 and 5 is in many respects similar to the one described in the foregoing. It comprises an upwardly tapering main reed 50 having an armature or weight 5| riveted or otherwise secured thereto. While the upper or stressed portion of the main reed is imperforate and has no weakened regions, the lower or clamped region thereof 52 has two holes 53 provided therein for the stack screws and also a transverse slot 54, which denes weakened hinge sections 55. To the intermediate portion of the main reed are secured by rivets 55 a pair of side arms 51 bearing vibratory contacts 58 at the ends thereof. As this particular vibratory structure is designed for a non-synchronous vibrator, only one vibratory contact is arranged at each side of the main reed. although the principles of the invention are applicable with obvious modifications to the construction of synchronous vibrators. A driver contact 59 is mounted at the end of auxiliary reed B0,

the lower portion of which is integrally extended to constitute a transverse clamping strip secured to the main reed on top of one of the correspcnd' ing side arms by means lof rivets 56.

This type of construction requires that the period of the driver contact spring 60 and driver contact weight be somewhat less than the frequency of main reed 50. If the period is too fast', the contacts open before they should causing an erratic or unstable action of the vibrator. If the contacts open considerably too late, however, the main contacts will make before the driver contacts open, snorting out the battery through the transformer primary or causing the reed to remain in the pull position, and therefore failure of the unit to vibrate. For this reason, a certain amount of part selection must be maintained on the driver arms and contacts to effect proper timing with respect to the remainder of the vibratory system. Experience has demonstrated that this selection is relatively non-critical and may be readily accomplished o'n a quantity production scale. It has 'been also found that the driver contact spring may be tuned so that it makes contact late thereby reducing the amount of coil current drawn without appreciably reducing the reed amplitude.

The operation of this modified vibratory system is-substantially the same as that of the previous embodiment with the only difference that in the first one break of the driver circuit is positively determined by ledge 40 of armature or weight 39 striking against the upper extremity of auxiliary reed 31 whereas in the embodiment of Figs. 4 and 5 the break of the driver circuit is determined by the natural frequency and timing of the auxiliary reed and vibratory driver contact.

The modiiled vibratory system illustrated in Iiigs. 6 and 7 is likewise designed for a non-synchronous vibrator and comprises an upwardly tapering main reed Il `carrying an armature or weight 1I at the upper end thereof. A pair of holes 13 are provided in the lower or clamped portion 12 of this reed and a transverse slot 14 defines a pair of weakened hinge sections 1I. Side arms 'I1 are secured to the twosides ofmain reed 1l and carry vibratory interrupter contacts 18 at the ends thereof. A vibratory driver contact 'I9 is mounted at the upper or free end of driver contact spring or auxiliary reed il, the lower portion of which extends transversely and is secured on top of the corresponding portion of one side arm by means of rivets 18. So far the construction of this embodiment is identical with that of the vibratory structure of Figs. 4 and 5. The diiference between the two forms of vibratory structure resides in the provision of a stop 82 of a substantially non-compliant character extending along the driver contact arm or auxiliary reed and preventing deflection thereof in that direction. Stop 82 is supported by an integral transverse lower extension similar to element Il of the auxiliary reed and likewise secured to the main reedA by rivets 10. It will be noted that when the main reed is displaced in one direction, the auxiliary reed will be aused to follow such displacement by stop 82 but during the return of the main reed the auxiliary reed may lag behind the main reed to obtain proper timing of the driver circuit operation. Otherwise the operation of this modified embodiment is self-explanatory.

It will be noted that the vibrator of the present invention provides a number of important advantages. First of all. the described novel and improved construction permits the use of a tapered main reed without any is principally subjected to strong bending stresses. The described and illustrated reed constructions eliminate the detrimental concentration of stresses in the critical regions. The elimination of any holes punched in the main reed in the bending or stressed portion eliminates reed breakages due to faulty dies causing the hardreed material to shatter around said punched holes. The provision of the driver contact system laterally of the main reed, rather than in the center thereof, as this was customary in conventional practice, allows easy access to the contacts for adjustment purposes. The various contacts of the vibrator of the invention may be made either flat to obtain contact wipe, or angled to prevent contact wipe.

The embodiments of the present invention shown in Figs. 1 to 3 and in Figs. 6 and 'I also have the added advantage of eliminating the necessity for synchronizing the driver contact, as a result of the positive timing of the auxiliary reed with respect to the operation of the main reed, such timing being assured by the cooperation of ledge 40 of the armature and the end of the auxiliary reed in the embodiment of Figs. 1 to 3, and by stop 82 in the embodiment of Figs. 6 and 7.

While the present invention, as to its objects and advantages, has been described herein as carried out in specific embodiments thereof, it is not desired to be limited thereby but it is intended to cover the invention broadly within the spirit and scope of the appended claims.

What is 'claimed is:

1. A vibratory electromagnetic interrupter comholes in the portion which prising in combination a main vibratory reed clamped at the lower end thereof. a ferromagnetic weight at the other end of said reed, an electromagnetic system adapted when energized to deiiectsaid weight and said reed, an auxiliary reed having one of its ends secured to said main reed and extending along the same at a substantial distance from the center line1 thereof. a vibratory driver contact at the other end of said auxiliary reed. a fixed driver contact adapted to cooperate with said vibratory driver contact to control said electromagnetic system and thereby to maintain said reeds in vibration, said main reed having a continuous and imperforate surface in its upper portion to avoid concentration of stresses in the regions subjected to strong flexing, and means on said main reed eneageable with said auxiliary reed during the travel of the main reed in driver contact-breaking direction whereby both reeds shall move as a unit during their travel in such direction and the auxiliary reed shall lag behind the main reed during the travel thereof in driver contact-closing direction.

2. A vibratory electromagnetic interrupter comprising in combination a main vibratory reed clamped at the lower end thereof and having a continuous and imperforate surface in its upper portion, an armature secured to the free end of said reed, a driver coil adapted when energized to deflect said reed, an auxiliary reed having one of its ends secured to said main reed at a distance from the center line thereof and bearing a vi bratory driver contact at its other end, said auxiliary reed being capable of limited but substantially independent vibration with respect to -saidmain reed, a stationary driver contact cooperating with said vibratory driver contact to control the flow of current through said driver coil thereby to maintain said reeds in timed vibratory motion, and means operatively associated with said main reed constructed and arranged to strike against the auxiliary reed during travel of the reeds in driver contact-breaking direction whereby both reeds shall move synchronously in the driver contact-making direction,

3. A driver contact vibrator comprising in combination a main vibratory reed having an imperforate upper portion and a clamped lower portion, an armature secured to the free end of said reed, a driver electromagnet for applying deilecting force to said armature, an auxiliary reed having one end secured to a region on said main reed in proximity to one of the side edges thereof vand extending in the direction of the main reed into the vibratory path of said armature, a vibratory driver contact on said auxiliary reed, and a stationary driver contact cooperating with said vibratory driver contact for controlling the circuit of said electromagnet, said driver contacts being normally closed'to close said circuit and being opened to interrupt said circuit upon the end of said auxiliary reed being engaged by said armature;

4. A driver contact vibrator comprising in combination a. main vibratory reed having a clamped lower portion and an imperforate upwardly tapering upper portion, an armature secured to the free end of said reed, a driver coil for deflecting said armature, an auxiliary reed having one end secured to said main reed in a lateral region where said tapering portion begins and having its other end extending into the vibratory path ofA said armature, a vibratory driver contact on said auxiliary reed, and a cooperating ilxed driver contact for controlling the circuit of said coil,

vibratory contact to control the aes'aoac said driver contacts being normally closed to energize said coil from a source of current and to deflect said armature and said contacts being opened with a predetermined time delay upon engagement of the free end of said auxiliary reed by the deflected armature.

5. A driver contact vibrator comprising in combination a main vibratory reed having a clamped lower portion and a generally imperi'orate upwardly tapering upper portion, an amature secured to the free end oi said reed and a driver coil therefor, an auxiliary reed having one end securedv to said main reed in a lateral region 'where said tapering portion begins and bearing a. vibratory driver contact at its other end, a iixed driver contact adapted to cooperate withthe said circuit oi' said coil thereby to maintain said reeds in vibration, and a stop mounted on said main reed and extending along said auxiliary reed, said stop beine engageabie with said auxiliary reed during travel of the reeds in driver contact-breaking direction to cause breaking the driver coll circuit in positively determined sequence with respect to the travel of the main reed.

6. A driver contact vibrator comprising' in combination a main vibratory reed, an electromagnety for deecting the free end of saidreed, an auxiliary reed having one end secured to a region on said main reed in proximity to one oi' .the side edges thereof so that it will extend in the direction of the main reed and carrying a vibratory contact at its other end, a relatively stationary contact mounted for cooperation with said vibratory contact for controlling the circuit of said electromagnet, and elements displaceable with said main reed engageable with the auxiliary reed during deflection of the main reed by said electromagnet, said contacts being normally closed to close said circuit and being opened to interrupt said circuit upon said auxiliary reed being engaged by said `displaceable elements.

7. A driver contact vibrator comprising in coinan. auxiliary reed mounted for generally inde-A pendent vibration on a region of the main reed one of the side edges thereof and extending in the direction of the main reed, a contact on the vibratory end of said auxiliary reed, a cooperating fixed contact for controlling the circuit of said coil, and elements permanently connected with said main reed engageable with said auxiliary reed during deection of the main reed to interrupt said circuit, said main and auxiliary reeds traveling as a single unit during said deflection, and the compliance and the natural frequency of said auxiliary reed being so determined with respect to those of the main reed that the auxiliary reed will lag behind the main reed during the return travel of said reeds.

ROBERT J. AUST. REFERENCES crran The following references are of record in the le of this patent:

UNITED 'STATES PATENTS 

